1211021984617 has 2 divisors, whose sum is σ = 1211021984618. Its totient is φ = 1211021984616.

The previous prime is 1211021984561. The next prime is 1211021984651. The reversal of 1211021984617 is 7164891201121.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1076082574336 + 134939410281 = 1037344^2 + 367341^2 .

It is a cyclic number.

It is not a de Polignac number, because 1211021984617 - 2³¹ = 1208874500969 is a prime.

It is not a weakly prime, because it can be changed into another prime (1211021984017) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 605510992308 + 605510992309.

It is an arithmetic number, because the mean of its divisors is an integer number (605510992309).

Almost surely, 2^{1211021984617} is an apocalyptic number.

It is an amenable number.

1211021984617 is a deficient number, since it is larger than the sum of its proper divisors (1).

1211021984617 is an equidigital number, since it uses as much as digits as its factorization.

1211021984617 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 48384, while the sum is 43.

The spelling of 1211021984617 in words is "one trillion, two hundred eleven billion, twenty-one million, nine hundred eighty-four thousand, six hundred seventeen".